IMMUNEMONITORINGANDANALYSISOFCANCERATSTANFORD(IMACS) Abstract The Center for Immune Monitoring and Analysis of Cancer at Stanford (IMACS) will perform highly comprehensiveassaysofimmunephenotypeandfunctionforNCI-identifiedclinicaltrials.Thesewillinclude standardized assays already developed on CyTOF, high-dimensional flow cytometry, Luminex, TCRseq, and RNAseq platforms. As part of the program we will also standardize and offer as assays Stanford-invented technologiesunderdevelopment,includingMultiplexedIonBeamImaging(MIBI)andAssaysofTransposon- AccessibleChromatin(ATAC-seq).Wehavedesignedourcenterstructuretoworkwithinvestigatorstodefine theassaysbestsuitedtotheimmunologicalquestionsbeingposed,andmatchthesewiththerequiredsample types.Wewillperformqualitycontrolmeasuresonallassays,aswellasgenerateastandardreportforeach assay and project. Data will be organized via our online database, Stanford Data Miner, to ensure data longevityandtransferability,aswellasaccesstobothrawdatafilesandanalyzedresults.Finally,wewillwork withinvestigatorsonnovelbioinformaticsapproachestominingthesehigh-dimensionaldatasets.Thesewill include approaches designed for a single data type (e.g., viSNE and Citrus for CyTOF and flow cytometry data),aswellasapproachesforintegratingdataacrossassays,usingappropriatemachinelearningalgorithms toaidNCIresearchersinidentifyingimmunehallmarkscentraltotheirtrials. Relevance:TheIMACScenterwillprovideaccesstoasuiteofstate-of-the-artimmuneassays,manyofthem developed or refined at Stanford. This unmatched set of technologies will facilitate the discovery of new biomarkers for predicting cancer outcome or therapeutic response, as well as defining potential new mechanismsofimmunecontrolofcancer.